Objective Surgical and medical (drug) treatment options exist for many conditions. Practitioners from different specialties often perform or prescribe these interventions, and it is unknown how often the options are directly compared in randomized clinical trials (RCTs). We aimed to investigate the prevalence of comparative effectiveness trials of surgical vs medical interventions by assessing Cochrane systematic reviews that address surgical interventions and recording whether they include RCTs comparing surgical interventions with medical interventions.

Methods We searched the Cochrane Library from inception until September 2015 to identify all published Cochrane meta-analyses of surgical interventions using the search term surg* in “search all text.” Only meta-analyses presenting evidence from RCTs were eligible. Medical intervention was defined as the administration of medication. Interventional radiology, dental, gastroenterologic, and cardiologic procedures were excluded. For Cochrane reviews meeting the criteria, we established the number of surgical vs medical RCTs used in the meta-analysis. We determined the standardized mean difference in effect size between surgical and medical interventions within each meta-analysis to assess which interventions showed overall better results.

Results Of 3475 reviews identified in our search, 33 including 54 unique RCTs of surgical vs medical interventions met inclusion criteria; in another 46, the authors intended to compare surgical and medical interventions but no RCTs were found. Across the 33 meta-analyses, medical intervention was found superior to surgical intervention for the primary outcome in 5, and surgical intervention was found superior to medical intervention in 9. The remaining 19 reviews were inconclusive.

Conclusions We identified a lack of RCTs directly comparing medical and surgical interventions. More such trials are needed to document whether surgical and medical interventions are equally good or one is better than the other in different conditions.